A structure of conventional cylindrical air-cell is explained below by referring FIG. 14 which shows a partly cutout side view of said air-cell. In FIG. 14, 101 is a cylindrical negative electrode containing an active material of so-called "jellied zinc" in which zinc powder is dispersed in jellied electrolyte, and 102 is a collector provided at the center of negative electrode 101. 103 is a multi-layered cylindrical positive electrode comprised of catalyst layer 104 containing manganese oxide and carbon material, collector layer 105 buried within catalyst layer 104, and a water-repellant porous layer 106 made of fluororesin contacting with a surface of catalyst layer 104.
The other surface of said catalyst layer 104 is faced to negative electrode 102 through separator 107, and is operated by utilizing the oxygen contained in air as an active material. 108 is a cylindrical positive electrode-can containing air-diffusing layer made of non-woven fabric covering the surface of said positive electrode 103, and other electricity generating elements including negative electrode 101 and positive electrode 103, and is provided with air-intake hole 110. 111 is an insulation tube covering the entire surface of said cylindrical positive electrode can 109, provided with air-intake hole 110 and air-intake window 112 which are connected to said air-intake hole 110.
113 is a seal closing said air-intake window 112 and 114 is a resin seal to which the bottom of positive electrode can 109 is bent and clamped. 115 is a bottom plate of the negative electrode terminal contacted with collector 102, 116 is a positive electrode cap-terminal contacted with the top of positive electrode 103, 117 is a cell cover, 118 is a grooved part, and 119 is a sealing material preventing the leakage of electrolyte.
Explaining this cell structure further, the upper edge of positive electrode 103 is inwardly bent at the rim of grooved part 118, and the bent part is contacted with the rim of positive electrode cap-terminal 118, and these are inserted into cell-cover 117, and the upper edge of positive electrode canister 109 is bent and clamped at the rim of cell-cover 117. The lower edge of positive electrode 103 is sealed by inserting the bottom of water repellant porous layer 106 of positive electrode 103 between the sealing body 114 and the positive electrode canister 109, and clamped.
By employing the above explained cell-structure, leakage of jellied electrolyte filled within the cylindrical positive electrode 103 and leakage of electrolyte containing the zinc powder filled in the negative electrode from the top to the bottom end of positive electrode canister 109 can be prevented.
However, when the top end of cylindrical positive electrode 103 consisted of collector 105, catalyst layer 104, and water repellant porous layer 106, is bent at a rim of groove 118 provided for the sealing, cracks of catalyst layer 104 may apt to be produced at the bending or wrinkles of water-repellant porous layer 108 are apt to take place, and as a result of this, complete seal of cell-cover 117 had been hard to accomplish.
Furthermore, since the sealing of bottom edge of positive electrode canister 109 is performed by clamping only the edge of water repellent porous layer 106 between the sealing body 114 and the positive electrode canister 109, cracks of edge of water repellent porous layer 108 are apt to be produced so that perfect seal had been hard to obtain.
Since the alkaline electrolyte has a strong tendency of creeping and leakage through minute wrinkles or cracks of seal if produced, leakage of electrolyte may take place easily during the storage period or during the usage thereof.
Moreover, the conduction from positive electrode 103 to positive electrode canister 109 is performed by the mechanical contact of positive electrode 103 and positive electrode cap terminal 116 accomplished by the bending of the top rim of positive electrode canister 109, these con,acts may become unstable by vibration or shock applied on the cell, making the electric-current supply unstable.